The FDA has approved the proton-pump inhibitor (PPI) dexlansoprazole (Kapidex - Takeda), a delayed release formulation of the R-enantiomer of lansoprazole (Prevacid - Takeda), for treating and maintaining healing of erosive esophagitis and for treatment of heartburn associated with non-erosive gastroesophageal reflux disease (GERD).

Esomeprazole magnesium (Nexium - AstraZeneca), the S-isomer of omeprazole (Prilosec), is the fifth benzimidazole proton pump inhibitor to become available in the United States. Omeprazole, which was the first, is going off patent this year.

The FDA recently cleared the AmpliChip CYP450 Test (Roche), which analyzes blood-derived DNA to detect genetic variations in the activity of cytochrome P450 (CYP) enzymes CYP2D6 and CYP2C19 and determines the metabolizer status of the patient. The test is intended to help guide clinicians in prescribing individualized drug therapy. About 25% of all drugs, including many antidepressants and antipsychotics, are substrates of either CYP2D6 or CYP2C19. The test is being promoted initially to psychiatrists.

Per capita spending on prescription drugs in the US is higher than in other industrialized nations, including Canada.

The FDA has approved vonoprazan (Voquezna – Phathom), a potassium-competitive acid blocker, for healing and maintenance of healing of all grades of erosive esophagitis and relief of associated heartburn in adults. Vonoprazan is also available copackaged with amoxicillin (Voquezna Dual Pak) and with amoxicillin and clarithromycin (Voquezna Triple Pak) for treatment of Helicobacter pylori infection in adults.

Pantoprazole, the fourth benzimidazole proton pump inhibitor to become available in the United States, has been marketed for short-term oral treatment of erosive gastroesophageal reflux disease (GERD).

Changes caused by one drug in the absorption, distribution, metabolism or excretion of another may lead to a pharmacokinetic adverse drug interaction (DN Juurlink et al, JAMA 2003; 289:1652). Additive drug interactions, such as vasodilation caused by both sildenafil (Viagra) and nitrates, can also have adverse effects.

Clopidogrel (Plavix), which prevents arterial thrombosis by inhibiting platelet activation, is commonly prescribed (usually with aspirin) for months after acute coronary syndromes and stent implantation. It may also, however, increase the risk of bleeding. Therefore, a proton pump inhibitor (PPI) such as omeprazole (Prilosec, and others) is often given concurrently to decrease the risk of gastrointestinal (GI) bleeding. Some reports have suggested that omeprazole may interfere with the antiplatelet effect of clopidogrel.

Aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs) are common causes of peptic ulcer disease. Patients infected with Helicobacter pylori who take aspirin or another NSAID have an especially high risk. Drugs that have been tried for prevention of ulcers in patients taking NSAIDs including H2-receptor antagonists, proton pump inhibitors (PPIs), aluminum- or magnesium-containing antacids, the prostaglandin misoprostol (Cytotec, and others), and antibiotics to eradicate H. pylori.Click here to view the free full...

Gastroesophageal reflux disease (GERD) is the most common GI condition encountered in the outpatient setting; it affects about 20% of people in the US.